Published 2010-07-27 · Federal Register document 2010-18009
Airworthiness Directives; The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 Series Airplanes
Publication summary
The FAA is superseding an existing airworthiness directive (AD), which applies to all Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. That AD currently requires repetitive inspections to find cracks, fractures, or corrosion of each carriage spindle of the left and right outboard mid-flaps, and corrective action if necessary. That AD also currently requires repetitive gap checks of the inboard and outboard carriage of the outboard mid-flaps to detect fractured carriage spindles, and corrective actions if necessary. This new AD requires any new or serviceable carriage spindle installed per the requirements of the existing AD to meet minimum allowable diameter measurements taken at three locations. This AD also requires new repetitive inspections, measurements, and overhaul of the carriage spindles, and applicable corrective actions. In addition, this AD requires replacing any carriage spindle when it has reached its maximum life limit. This AD results from reports of fractures that resulted from stress corrosion and pitting along the length of the spindle and spindle diameter, and additional reports of corrosion on the outboard flap carriage spindles. We are issuing this AD to detect and correct cracked, corroded, or fractured carriage spindles, and to prevent severe flap asymmetry, which could result in reduced control or loss of controllability of the airplane.
Why this record is shown
Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:33.146842+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_2010-a7267cd3a71dbd26
- Source row
- results[231]
- Raw source SHA-256
- a7267cd3a71dbd2645583c8a673df65e4a7fa9360a96e3be0de5b81f9d68c9a0
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2010-15-08
- Effective date printed in this edition
- 2010-08-31
Read 13 complete recorded clauses
Effective Date
Effective Date
(a) This AD becomes effective August 31, 2010.
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Affected ADs
Affected ADs
(b) This AD supersedes AD 2003-24-08, Amendment 39-13377.
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Applicability wording · Applicability
Applicability
(c) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in
any category.
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Subject
Subject
(d) Air Transport Association (ATA) of America Code 57: Wings.
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Unsafe Condition
Unsafe Condition
(e) This AD results from a report indicating that the inboard
and outboard carriage spindles were fractured on the right outboard
flap during approach to landing. We are issuing this AD to detect
and correct cracked, corroded, or fractured carriage spindles and to
prevent severe flap asymmetry, which could result in reduced control
or loss of controllability of the airplane.
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Compliance
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
RESTATEMENT OF CERTAIN REQUIREMENTS OF AD 2003-24-08, WITH UPDATED
SERVICE INFORMATION
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Compliance Times
Compliance Times
(g) The tables in paragraph 1.E., ``Compliance'' of Boeing Alert
Service Bulletin 737-57A1277, Revision 1, dated November 25, 2003,
specify the compliance times for paragraphs (g) through (k) of this
AD. For carriage spindles that have accumulated the number of flight
cycles or years in service specified in the ``Threshold'' column of
the tables, accomplish the gap check and nondestructive test (NDT)
and general visual inspections specified in paragraphs (h) and (j)
of this AD within the corresponding interval after December 4, 2003
(the effective date AD 2003-24-08), as specified in the ``Interval''
column. Repeat the gap check and NDT and general visual inspections
at the same intervals, except:
(1) The gap check does not have to be done at the same time as
an NDT inspection; after doing an NDT inspection, the interval for
doing the next gap check can be measured from the NDT inspection;
and
(2) As carriage spindles gain flight cycles or years in service
and move from one category in the ``Threshold'' column to another,
they are subject to the repetitive inspection intervals
corresponding to the new threshold category.
Work Package 2: Gap Check
(h) Perform a gap check of the inboard and outboard carriage of
the left and right outboard mid-flaps to determine if there is a
positive indication of a severed carriage spindle, in accordance
with Work Package 2 of paragraph 3.B., ``Work Instructions'' of
Boeing Alert Service Bulletin 737-57A1277, Revision 1, dated
November 25, 2003.
Work Package 2: Corrective Actions
(i) If there is a positive indication of a severed carriage
spindle during the gap check required by paragraph (h) of this AD,
before further flight, remove the carriage spindle and install a new
or serviceable carriage spindle in accordance with the ``Work
Instructions'' of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003; or Boeing Alert Service
Bulletin 737-57A1218, Revision 5, dated February 9, 2009. If, as a
result of the detailed inspection described in paragraph 4.b. of
Work Package 2 of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003, a carriage spindle is found not
to be severed and no corrosion and no cracking is present, it can be
reinstalled on the mid-flap in accordance with Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003; or Boeing
Alert Service Bulletin 737-57A1218, Revision 5, dated February 9,
2009. After the effective date of this AD, use only Boeing Alert
Service Bulletin 737-57A1218, Revision 5, dated February 9, 2009.
Work Package 1: Inspections
(j) Perform a NDT inspection and general visual inspection for
each carriage spindle of the left and right outboard mid-flaps to
detect cracks, corrosion, or severed carriage spindles, in
accordance with the ``Work Instructions'' of Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003.
Work Package 1: Corrective Actions
(k) If any corroded, cracked, or severed carriage spindle is
found during any inspection required by paragraph (j) of this AD,
before further flight, remove the carriage
[[Page 43806]]
spindle and install a new or serviceable carriage spindle in
accordance with the ``Work Instructions'' of Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003; or Boeing
Alert Service Bulletin 737-57A1218, Revision 5, dated February 9,
2009. After the effective date of this AD, use only Boeing Alert
Service Bulletin 737-57A1218, Revision 5, dated February 9, 2009.
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Parts Installation
Parts Installation
(l) Except as provided in paragraph (i) of this AD: As of
December 4, 2003, no person may install on any airplane a carriage
spindle that has been removed as required by paragraph (i) or (k) of
this AD, unless it has been overhauled in accordance with the ``Work
Instructions'' of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003; or Boeing Alert Service
Bulletin 737-57A1218, Revision 5, dated February 9, 2009. After the
effective date of this AD, use only Boeing Alert Service Bulletin
737-57A1218, Revision 5, dated February 9, 2009. To be eligible for
installation under this paragraph, the carriage spindle must have
been overhauled in accordance with the requirements of paragraph (m)
of this AD.
(m) During accomplishment of any overhaul specified in paragraph
(l) of this AD, use the procedures specified in paragraphs (m)(1)
and (m)(2) of this AD during application of the nickel plating to
the carriage spindle in addition to those specified in Chapter 20-
42-09, Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual. As of the effective date of this AD, use
only Chapter 20-42-09, Electrodeposited Nickel Plating, of the
Boeing (737) Standard Overhaul Practices Manual, Revision 25, dated
July 1, 2009.
(1) The maximum deposition rate of the nickel plating in any one
plating/baking cycle must not exceed 0.002-inches-per-hour.
(2) Begin the hydrogen embrittlement relief bake within 10 hours
after application of the plating, or less than 24 hours after the
current was first applied to the part, whichever is first.
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Exception to Reporting Recommendations in Certain Service Bulletins
Exception to Reporting Recommendations in Certain Service Bulletins
(n) Although Boeing Alert Service Bulletin 737-57A1277, Revision
1, dated November 25, 2003, recommends that operators report
inspection findings to the manufacturer, this AD does not contain
such a reporting requirement.
NEW ACTIONS REQUIRED BY THIS AD
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Inspections, Measurements, and Overhauls of the Carriage Spindle
Inspections, Measurements, and Overhauls of the Carriage Spindle
(o) At the applicable times specified in paragraph (o)(1) or
(o)(2) of this AD: Do the detailed inspection for corrosion,
pitting, and cracking of the carriage spindle, the magnetic particle
inspection for cracking of the carriage spindle, measurements of the
spindle to determine if it meets the allowable minimum diameter, and
overhauls, and applicable corrective actions by accomplishing all
the applicable actions specified in the Accomplishment Instructions
of Boeing Alert Service Bulletin 737-57A1218, Revision 5, dated
February 9, 2009. The applicable corrective actions must be done
before further flight. Repeat these actions thereafter at intervals
not to exceed 12,000 flight cycles on the carriage spindle or 8
years, whichever comes first.
(1) For Model 737-100, -200, -200C series airplanes, at the
later of the times specified in paragraph (o)(1)(i) or (o)(1)(ii) of
this AD:
(i) Before the accumulation of 12,000 total flight cycles on the
carriage spindle since new or overhauled, or within 8 years after
the installation of the new or overhauled part, whichever comes
first.
(ii) Within 1 year after the effective date of this AD.
(2) For Model -300, -400, and -500 series airplanes, at the
later of the times specified in paragraph (o)(2)(i) or (o)(2)(ii) of
this AD:
(i) Before the accumulation of 12,000 total flight cycles on the
carriage spindle since new or overhauled, or within 8 years after
the installation of the new or overhauled part, whichever comes
first.
(ii) Within 2 years after the effective date of this AD.
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Replacement of the Carriage Spindle
Replacement of the Carriage Spindle
(p) For Model 737-100, -200, -200C series airplanes: Replace the
carriage spindle with a new or documented (for which the service
life, in total flight cycles, is known) carriage spindle, in
accordance with Boeing Alert Service Bulletin 737-57A1218, Revision
5, dated February 9, 2009, at the later of the times specified in
paragraphs (p)(1) and (p)(2) of this AD, except as required by
paragraph (r) of this AD. Overhauling the carriage spindles does not
zero-out the flight cycles. Total flight cycles accumulate since
new.
(1) Before the accumulation of 48,000 total flight cycles on the
new or overhauled carriage.
(2) Within three years or 7,500 flight cycles after the
effective date of this AD, whichever occurs first.
(q) For Model 737-300, -400, and -500 series airplanes: Replace
the carriage spindle with a new or documented (for which the service
life, in flight cycles, is known) carriage spindle, in accordance
with Boeing Alert Service Bulletin 737-57A1218, Revision 5, dated
February 9, 2009, at the later of the times specified in paragraphs
(q)(1) and (q)(2) of this AD, except as required by paragraph (r) of
this AD. Overhauling the carriage spindles does not zero-out the
flight cycles. Total flight cycles accumulate since new.
(1) Before the accumulation of 48,000 total flight cycles on the
new or overhauled carriage.
(2) Within six years or 15,000 flight cycles after the effective
date of this AD, whichever occurs first.
(r) For airplanes with an undocumented carriage: Do the
applicable actions specified in paragraph (p) or (q) of this AD at
the applicable time specified in paragraph (r)(1) or (r)(2) of this
AD.
(1) For Model 737-100, -200, -200C series airplanes: Do the
actions specified in paragraph (p) of this AD at the time specified
in paragraph (p)(2) of this AD.
(2) For Model -300, -400, and -500 series airplanes: Do the
actions specified in paragraph (q) of this AD at the time specified
in paragraph (q)(2) of this AD.
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Repetitive Replacements of Carriage Spindle
Repetitive Replacements of Carriage Spindle
(s) For all airplanes: Repeat the replacement of the carriage
spindle specified by paragraph (p) or (q) of this AD, as applicable,
thereafter at intervals not to exceed 48,000 total flight cycles on
the new or overhauled carriage spindle.
Alternative Methods of Compliance (AMOCs)
(t)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. Send information to
ATTN: Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S,
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW.,
Renton, Washington 98057-3356; telephone (425) 917-6440; fax (425)
917-6590. Or, e-mail information to [email protected].
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
(3) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD, if it is approved by the
Boeing Commercial Airplanes Organization Designation Authorization
(ODA) that has been authorized by the Manager, Seattle ACO, to make
those findings. For a repair method to be approved, the repair must
meet the certification basis of the airplane, and the approval must
specifically refer to this AD.
(4) AMOCs previously approved in accordance with AD 2003-24-08,
Amendment 39-13377, for individual repairs are acceptable for
compliance with the corresponding provisions of this AD. All other
existing AMOCs are not acceptable.
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Material Incorporated by Reference
Material Incorporated by Reference
(u) You must use Boeing Alert Service Bulletin 737-57A1218,
Revision 5, dated February 9, 2009; Boeing Alert Service Bulletin
737-57A1277, Revision 1, dated November 25, 2003; and Chapter 20-42-
09, Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual, Revision 25, dated July 1, 2009, to do
the actions required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of Boeing Alert Service Bulletin 737-
57A1218, Revision 5, dated February 9, 2009; and Chapter 20-42-09,
Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual, Revision 25, dated July 1, 2009; under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) The Director of the Federal Register previously approved the
incorporation by
[[Page 43807]]
reference of Boeing Alert Service Bulletin 737-57A1277, Revision 1,
dated November 25, 2003, on December 4, 2003 (68 FR 67027, December
1, 2003).
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone
206-544-5000, extension 1; fax 206-766-5680; e-mail
[email protected]; Internet https://www.myboeingfleet.com.
(4) You may review copies of the service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington. For information on the availability of this material at
the FAA, call 425-227-1221.
(5) You may also review copies of the service information that
is incorporated by reference at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
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No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.
Find all recorded historical references to AD 2010-15-08 · 1 printed reference observations in this pinned collection.
These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.
Why these observations are shown
They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.
Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 057d6a9c7cc4a586141d7160754c3eeae314d11e212087dc9839ac5359343715. Source manifest: 1c9e00e2733cddff7d4c01bd009dfd7f9558cea943d6f6d52d87e7e3ac0112f5.
Official source · 2010-07-27
Publication text
This is the complete recorded text of this dated publication.
Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.
Read the complete official publication text
[Federal Register Volume 75, Number 143 (Tuesday, July 27, 2010)]
[Rules and Regulations]
[Pages 43803-43807]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-18009]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0173; Directorate Identifier 2009-NM-076-AD;
Amendment 39-16374; AD 2010-15-08]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 737-100, -200,
-200C, -300, -400, and -500 Series Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is superseding an existing airworthiness directive
(AD), which applies to all Model 737-100, -200, -200C, -300, -400, and
-500 series airplanes. That AD currently requires repetitive
inspections to find cracks, fractures, or corrosion of each carriage
spindle of the left and right outboard mid-flaps, and corrective action
if necessary. That AD also currently requires repetitive gap checks of
the inboard and outboard carriage of the outboard mid-flaps to detect
fractured carriage spindles, and corrective actions if necessary. This
new AD requires any new or serviceable carriage spindle installed per
the requirements of the existing AD to meet minimum allowable diameter
measurements taken at three locations. This AD also requires new
repetitive inspections, measurements, and overhaul of the carriage
spindles, and applicable corrective actions. In addition, this AD
requires replacing any carriage spindle when it has reached its maximum
life limit. This AD results from reports of fractures that resulted
from stress corrosion and pitting along the length of the spindle and
spindle diameter, and additional reports of corrosion on the outboard
flap carriage spindles. We are issuing this AD to detect and correct
cracked, corroded, or fractured carriage spindles, and to prevent
severe flap asymmetry, which could result in reduced control or loss of
controllability of the airplane.
DATES: This AD becomes effective August 31, 2010.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the AD as of August 31,
2010.
On December 4, 2003 (68 FR 67027, December 1, 2003), the Director
of the Federal Register approved the incorporation by reference of a
certain other publication listed in the AD.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management, P.
O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail [email protected];
Internet https://www.myboeingfleet.com.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (telephone 800-647-5527) is the Document Management
Facility, U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Nancy Marsh, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6440; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to include an AD that supersedes AD 2003-24-08, Amendment
39-13377 (68 FR 67027, December 1, 2003). The existing AD applies to
all Model 737-100, -200, -200C, -300, -400, and -500 series airplanes.
That NPRM was published in the Federal Register on March 1, 2010 (75 FR
9137). That NPRM proposed to continue to require repetitive gap checks
of the inboard and outboard carriage of the outboard mid-flaps to
detect fractured carriage spindles, and corrective actions if
necessary, and continue to require repetitive inspections to find
cracks, factures, or corrosion of each carriage spindle of the left and
right outboard mid-flaps. That NPRM also proposed to require any new or
serviceable carriage spindle installed per the requirements of the
existing AD to meet minimum allowable diameter measurements taken at
three locations. That NPRM proposed to require new repetitive
inspections, measurements, and overhaul of the carriage spindles, and
applicable corrective actions. In addition, that NPRM also proposed to
require replacing any carriage spindle
[[Page 43804]]
when it has reached its maximum life limit.
Actions Since Original NPRM Was Issued
Since we issued the original NPRM, there has been an in-service
event of a dual fracture of the outboard flap carriages. This event is
currently under investigation. As a result, we consider this AD to be
interim action. If final action is later identified, we might consider
further rulemaking then.
Explanation of Changes to AD
We have added paragraph (t)(4) to this final rule to provide credit
for actions done in accordance with previously issued AMOCs for
individual repairs. In paragraph (m) of this AD, we have also
referenced the most current issue of the Boeing (737) Standard Overhaul
Practices Manual for actions done as of the effective date of this AD.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments that have been
received on the NPRM.
Support for the NPRM
Boeing supports the intent of the NPRM.
Request for Stricter Inspection and Overhaul Limits in Lieu of Life
Limits
Safair states that it has experienced only one flap carriage
spindle failure before AD 2003-24-08 was issued. Safair states that its
main concern is scrapping serviceable carriages in order to enforce the
life limits on the flap carriages. Safair states that stricter
inspections and overhaul requirements would ensure that stress and
pitting corrosion are detected and corrected, which would avoid
failures and would extend the life of the flap carriages.
We do not agree that substituting stricter inspection and overhaul
limits for life limits would address the unsafe condition. Since AD
2003-24-08 was issued, we have received many additional reports of
carriage spindle fractures, including fractures caused by fatigue.
Because of the difficulty in detecting small cracks and the rapid crack
growth in these parts, in combination with the concerns with reduced
fatigue life of reworked and overhauled parts, the most effective way
to maintain the continued operational safety of the fleet is to mandate
life limits. We have not changed the AD in regard to this issue.
Request for Clarification of Requirements to Remove Flap Carriage
KLM requests clarification concerning the requirements to remove
the carriage spindle in order to perform a detailed inspection for
corrosion, pitting, cracking, and measurement of some minimal allowable
spindle diameters. KLM points out that the times specified for this
action are the same as for the initial gap check and the nondestructive
test for new carriage spindles. KLM asks whether the removal of the
carriage spindle is required at 12,000 flight cycles, if the initial or
repetitive gap check and the non-destructive test (NDT) at the same
time are still useful. KLM further states that carriage spindles that
receive a thorough detailed inspection and have been found to be
serviceable do not require a gap check or an NDT inspection at the
times specified in the 12,000- to 20,000-flight-cycle range as
specified in Table 1 and Table 2 of Boeing Alert Service Bulletin 737-
57A1277, Revision 1, dated November 25, 2003. KLM states that the gap
checks and NDTs are still required, although at a different time
interval after completing the requirements of paragraph (o) of the
NPRM.
We agree that clarification might be necessary. Paragraph (o) of
this final rule requires the overhaul to be performed on the new
carriage spindle before the accumulation of 12,000 flight cycles.
Therefore, the new carriage spindle should not accumulate more than
11,999 flight cycles before being overhauled in order to comply with
this requirement. Paragraph (g) of this AD refers to Boeing Alert
Service Bulletin 737-57A1277, Revision 1, dated November 25, 2003, for
the compliance times for the gap checks and NDT inspections. Boeing
Alert Service Bulletin 737-57A1277, Revision 1, dated November 25,
2003, states that the gap check and NDT inspections are not required
for a new flap carriage spindle that has accumulated fewer than 12,000
flight cycles without being overhauled.
Boeing Alert Service Bulletin 737-57A1277, Revision 1, dated
November 25, 2003, requires relatively stringent gap checks and NDT
inspections for flap carriage spindles that have accumulated 12,000 or
more flight cycles on them since being overhauled. This requirement
should become obsolete as this AD requires that all spindles be
overhauled before accumulating 12,000 flight cycles since new or
overhauled.
We have not changed the AD in regard to this issue.
Conclusion
We have carefully reviewed the available data, including the
comments that have been received, and determined that air safety and
the public interest require adopting the AD with the changes described
previously. We have determined that these changes will neither increase
the economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
There are about 2,852 airplanes of the affected design in the
worldwide fleet. The following table provides the estimated costs for
U.S. operators to comply with this AD.
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Number of
Average U.S.-
Action Work hours labor rate Parts Cost per airplane registered Fleet cost
per hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspections (required by AD 2003-24- 12 $85 None $1,020 per inspection 652 $665,040 per inspection cycle.
08). cycle.
Inspections and measurements (new 2 85 None $170 per inspection 652 $110,840 per inspection and measurement
actions). and measurement cycle. cycle.
Overhauls (new actions)............ 16 85 \1\ 28,000 $29,360 per overhaul 652 $19,142,720 per overhaul cycle.
cycle.
Replacements (new actions)......... 16 85 \2\ 60,000 $61,360 per 652 $40,006,720 per replacement cycle.
replacement cycle....
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ $7,000 per spindle; 4 spindles per airplane.
\2\ $15,000 per spindle; 4 spindles per airplane.
[[Page 43805]]
The cost impact figures discussed above are based on assumptions
that no operator has yet accomplished any of the actions required by
this AD, and that no operator would accomplish those actions in the
future if this AD were not adopted. However, we have been advised that
the carriage spindles are already being overhauled and replaced on some
affected airplanes. In addition, the replacement cycle is approximately
every 20 years. Therefore, the future economic cost impact of this rule
on U.S. operators is expected to be less than the cost impact figures
indicated above.
Authority for this Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, Section 106, describes the
authority of the FAA Administrator. Subtitle VII, Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701, ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will not have a
substantial direct effect on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and
(3) Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to
comply with this AD and placed it in the AD docket. See the ADDRESSES
section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by
removing Amendment 39-13377 (68 FR 67027, December 1, 2003) and by
adding the following new airworthiness directive (AD):
2010-15-08 The Boeing Company: Amendment 39-16374. Docket No. FAA-
2010-0173; Directorate Identifier 2010-NM-076-AD.
Effective Date
(a) This AD becomes effective August 31, 2010.
Affected ADs
(b) This AD supersedes AD 2003-24-08, Amendment 39-13377.
Applicability
(c) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in
any category.
Subject
(d) Air Transport Association (ATA) of America Code 57: Wings.
Unsafe Condition
(e) This AD results from a report indicating that the inboard
and outboard carriage spindles were fractured on the right outboard
flap during approach to landing. We are issuing this AD to detect
and correct cracked, corroded, or fractured carriage spindles and to
prevent severe flap asymmetry, which could result in reduced control
or loss of controllability of the airplane.
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
RESTATEMENT OF CERTAIN REQUIREMENTS OF AD 2003-24-08, WITH UPDATED
SERVICE INFORMATION
Compliance Times
(g) The tables in paragraph 1.E., ``Compliance'' of Boeing Alert
Service Bulletin 737-57A1277, Revision 1, dated November 25, 2003,
specify the compliance times for paragraphs (g) through (k) of this
AD. For carriage spindles that have accumulated the number of flight
cycles or years in service specified in the ``Threshold'' column of
the tables, accomplish the gap check and nondestructive test (NDT)
and general visual inspections specified in paragraphs (h) and (j)
of this AD within the corresponding interval after December 4, 2003
(the effective date AD 2003-24-08), as specified in the ``Interval''
column. Repeat the gap check and NDT and general visual inspections
at the same intervals, except:
(1) The gap check does not have to be done at the same time as
an NDT inspection; after doing an NDT inspection, the interval for
doing the next gap check can be measured from the NDT inspection;
and
(2) As carriage spindles gain flight cycles or years in service
and move from one category in the ``Threshold'' column to another,
they are subject to the repetitive inspection intervals
corresponding to the new threshold category.
Work Package 2: Gap Check
(h) Perform a gap check of the inboard and outboard carriage of
the left and right outboard mid-flaps to determine if there is a
positive indication of a severed carriage spindle, in accordance
with Work Package 2 of paragraph 3.B., ``Work Instructions'' of
Boeing Alert Service Bulletin 737-57A1277, Revision 1, dated
November 25, 2003.
Work Package 2: Corrective Actions
(i) If there is a positive indication of a severed carriage
spindle during the gap check required by paragraph (h) of this AD,
before further flight, remove the carriage spindle and install a new
or serviceable carriage spindle in accordance with the ``Work
Instructions'' of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003; or Boeing Alert Service
Bulletin 737-57A1218, Revision 5, dated February 9, 2009. If, as a
result of the detailed inspection described in paragraph 4.b. of
Work Package 2 of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003, a carriage spindle is found not
to be severed and no corrosion and no cracking is present, it can be
reinstalled on the mid-flap in accordance with Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003; or Boeing
Alert Service Bulletin 737-57A1218, Revision 5, dated February 9,
2009. After the effective date of this AD, use only Boeing Alert
Service Bulletin 737-57A1218, Revision 5, dated February 9, 2009.
Work Package 1: Inspections
(j) Perform a NDT inspection and general visual inspection for
each carriage spindle of the left and right outboard mid-flaps to
detect cracks, corrosion, or severed carriage spindles, in
accordance with the ``Work Instructions'' of Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003.
Work Package 1: Corrective Actions
(k) If any corroded, cracked, or severed carriage spindle is
found during any inspection required by paragraph (j) of this AD,
before further flight, remove the carriage
[[Page 43806]]
spindle and install a new or serviceable carriage spindle in
accordance with the ``Work Instructions'' of Boeing Alert Service
Bulletin 737-57A1277, Revision 1, dated November 25, 2003; or Boeing
Alert Service Bulletin 737-57A1218, Revision 5, dated February 9,
2009. After the effective date of this AD, use only Boeing Alert
Service Bulletin 737-57A1218, Revision 5, dated February 9, 2009.
Parts Installation
(l) Except as provided in paragraph (i) of this AD: As of
December 4, 2003, no person may install on any airplane a carriage
spindle that has been removed as required by paragraph (i) or (k) of
this AD, unless it has been overhauled in accordance with the ``Work
Instructions'' of Boeing Alert Service Bulletin 737-57A1277,
Revision 1, dated November 25, 2003; or Boeing Alert Service
Bulletin 737-57A1218, Revision 5, dated February 9, 2009. After the
effective date of this AD, use only Boeing Alert Service Bulletin
737-57A1218, Revision 5, dated February 9, 2009. To be eligible for
installation under this paragraph, the carriage spindle must have
been overhauled in accordance with the requirements of paragraph (m)
of this AD.
(m) During accomplishment of any overhaul specified in paragraph
(l) of this AD, use the procedures specified in paragraphs (m)(1)
and (m)(2) of this AD during application of the nickel plating to
the carriage spindle in addition to those specified in Chapter 20-
42-09, Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual. As of the effective date of this AD, use
only Chapter 20-42-09, Electrodeposited Nickel Plating, of the
Boeing (737) Standard Overhaul Practices Manual, Revision 25, dated
July 1, 2009.
(1) The maximum deposition rate of the nickel plating in any one
plating/baking cycle must not exceed 0.002-inches-per-hour.
(2) Begin the hydrogen embrittlement relief bake within 10 hours
after application of the plating, or less than 24 hours after the
current was first applied to the part, whichever is first.
Exception to Reporting Recommendations in Certain Service Bulletins
(n) Although Boeing Alert Service Bulletin 737-57A1277, Revision
1, dated November 25, 2003, recommends that operators report
inspection findings to the manufacturer, this AD does not contain
such a reporting requirement.
NEW ACTIONS REQUIRED BY THIS AD
Inspections, Measurements, and Overhauls of the Carriage Spindle
(o) At the applicable times specified in paragraph (o)(1) or
(o)(2) of this AD: Do the detailed inspection for corrosion,
pitting, and cracking of the carriage spindle, the magnetic particle
inspection for cracking of the carriage spindle, measurements of the
spindle to determine if it meets the allowable minimum diameter, and
overhauls, and applicable corrective actions by accomplishing all
the applicable actions specified in the Accomplishment Instructions
of Boeing Alert Service Bulletin 737-57A1218, Revision 5, dated
February 9, 2009. The applicable corrective actions must be done
before further flight. Repeat these actions thereafter at intervals
not to exceed 12,000 flight cycles on the carriage spindle or 8
years, whichever comes first.
(1) For Model 737-100, -200, -200C series airplanes, at the
later of the times specified in paragraph (o)(1)(i) or (o)(1)(ii) of
this AD:
(i) Before the accumulation of 12,000 total flight cycles on the
carriage spindle since new or overhauled, or within 8 years after
the installation of the new or overhauled part, whichever comes
first.
(ii) Within 1 year after the effective date of this AD.
(2) For Model -300, -400, and -500 series airplanes, at the
later of the times specified in paragraph (o)(2)(i) or (o)(2)(ii) of
this AD:
(i) Before the accumulation of 12,000 total flight cycles on the
carriage spindle since new or overhauled, or within 8 years after
the installation of the new or overhauled part, whichever comes
first.
(ii) Within 2 years after the effective date of this AD.
Replacement of the Carriage Spindle
(p) For Model 737-100, -200, -200C series airplanes: Replace the
carriage spindle with a new or documented (for which the service
life, in total flight cycles, is known) carriage spindle, in
accordance with Boeing Alert Service Bulletin 737-57A1218, Revision
5, dated February 9, 2009, at the later of the times specified in
paragraphs (p)(1) and (p)(2) of this AD, except as required by
paragraph (r) of this AD. Overhauling the carriage spindles does not
zero-out the flight cycles. Total flight cycles accumulate since
new.
(1) Before the accumulation of 48,000 total flight cycles on the
new or overhauled carriage.
(2) Within three years or 7,500 flight cycles after the
effective date of this AD, whichever occurs first.
(q) For Model 737-300, -400, and -500 series airplanes: Replace
the carriage spindle with a new or documented (for which the service
life, in flight cycles, is known) carriage spindle, in accordance
with Boeing Alert Service Bulletin 737-57A1218, Revision 5, dated
February 9, 2009, at the later of the times specified in paragraphs
(q)(1) and (q)(2) of this AD, except as required by paragraph (r) of
this AD. Overhauling the carriage spindles does not zero-out the
flight cycles. Total flight cycles accumulate since new.
(1) Before the accumulation of 48,000 total flight cycles on the
new or overhauled carriage.
(2) Within six years or 15,000 flight cycles after the effective
date of this AD, whichever occurs first.
(r) For airplanes with an undocumented carriage: Do the
applicable actions specified in paragraph (p) or (q) of this AD at
the applicable time specified in paragraph (r)(1) or (r)(2) of this
AD.
(1) For Model 737-100, -200, -200C series airplanes: Do the
actions specified in paragraph (p) of this AD at the time specified
in paragraph (p)(2) of this AD.
(2) For Model -300, -400, and -500 series airplanes: Do the
actions specified in paragraph (q) of this AD at the time specified
in paragraph (q)(2) of this AD.
Repetitive Replacements of Carriage Spindle
(s) For all airplanes: Repeat the replacement of the carriage
spindle specified by paragraph (p) or (q) of this AD, as applicable,
thereafter at intervals not to exceed 48,000 total flight cycles on
the new or overhauled carriage spindle.
Alternative Methods of Compliance (AMOCs)
(t)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. Send information to
ATTN: Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S,
FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW.,
Renton, Washington 98057-3356; telephone (425) 917-6440; fax (425)
917-6590. Or, e-mail information to [email protected].
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
(3) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD, if it is approved by the
Boeing Commercial Airplanes Organization Designation Authorization
(ODA) that has been authorized by the Manager, Seattle ACO, to make
those findings. For a repair method to be approved, the repair must
meet the certification basis of the airplane, and the approval must
specifically refer to this AD.
(4) AMOCs previously approved in accordance with AD 2003-24-08,
Amendment 39-13377, for individual repairs are acceptable for
compliance with the corresponding provisions of this AD. All other
existing AMOCs are not acceptable.
Material Incorporated by Reference
(u) You must use Boeing Alert Service Bulletin 737-57A1218,
Revision 5, dated February 9, 2009; Boeing Alert Service Bulletin
737-57A1277, Revision 1, dated November 25, 2003; and Chapter 20-42-
09, Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual, Revision 25, dated July 1, 2009, to do
the actions required by this AD, unless the AD specifies otherwise.
(1) The Director of the Federal Register approved the
incorporation by reference of Boeing Alert Service Bulletin 737-
57A1218, Revision 5, dated February 9, 2009; and Chapter 20-42-09,
Electrodeposited Nickel Plating, of the Boeing (737) Standard
Overhaul Practices Manual, Revision 25, dated July 1, 2009; under 5
U.S.C. 552(a) and 1 CFR part 51.
(2) The Director of the Federal Register previously approved the
incorporation by
[[Page 43807]]
reference of Boeing Alert Service Bulletin 737-57A1277, Revision 1,
dated November 25, 2003, on December 4, 2003 (68 FR 67027, December
1, 2003).
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone
206-544-5000, extension 1; fax 206-766-5680; e-mail
[email protected]; Internet https://www.myboeingfleet.com.
(4) You may review copies of the service information at the FAA,
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington. For information on the availability of this material at
the FAA, call 425-227-1221.
(5) You may also review copies of the service information that
is incorporated by reference at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
Issued in Renton, Washington, on July 14, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-18009 Filed 7-26-10; 8:45 am]
BILLING CODE 4910-13-P
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